Forming machines are machine tools which, with the aid of suitable tools, can produce larger or smaller series of molded parts, sometimes of complex geometry, from semi-finished products such as wire, pipe, strip or the like, predominantly by forming in an automatic fabrication process. For example, a forming machine may be a bending machine that produces bent parts from wire material, strip material or pipe material or a spring machine that manufactures compression springs, tension spring members, torsion springs or other spring-like molded parts. A forming machine may also be designed, for example, as a machine to make wire nails for the mass production of screws, nails, rivets or the like.
A multiaxis forming machine controlled by computer numerical control has a plurality of controllable machine axes, a drive system with a plurality of electric drives that drive the machine axes, and a control device for the coordinated control of movements of the machine axes during a fabrication process according to a computer-readable control program specific for the fabrication process.
The movements provided for manufacture of the molded part and the sequence thereof are stored in this control program in the form of NC sets, which can be programmed differently (for example, machine-oriented or machine-independent). The control program is executed during the fabrication process for each molded part of a series, converted into control signals for the drives, and thus produces coordinated axial movements of the machine axes.
With some forming machines there is the possibility to undertake workpiece-based programming. With workpiece-based programming geometrical data can be input via an operator unit, the data describing the desired geometry (target geometry) of the molded part to be produced. When fabricating bent parts made from wire (for example, compression springs, torsion springs, spiral springs and other wire bent parts), the wire diameter and wire cross-section, the diameter of a finished spring, the number of windings of a spring, the pitch of a spring, angle of bend and/or lengths of a bent part and the like can be input, for example. The geometrical data is converted into a sequence of NC sets of the NC control program by an NC generator. It is therefore no longer necessary for an operator to access the level of the individual sentences to create the control program. If smaller changes are to be made to the program course and cannot be controlled by these input parameters or corresponding correction values, the NC program must be manipulated at NC set level, for example, to change an NC set or add a new NC set. The machine operator must have programming knowledge to do this.
EP 1 148 398 B1 describes an input method to program axial movements and events in industrial control systems which, in addition to manual input aids, also have a screen for visualizing the input process and displaying resultant actions. During this procedure, (a) editable blank diagrams for path/time curves for each axis and/or path/path relationships for pairs of master and slave axes are displayed to the user, and then (b) the path and time limits and/or path and time units are defined as needed, then (c) the path/time curves and/or the path/path relationships are entered into the diagrams by the input aids, and then the control program and/or the control code for the production process is generated by the control according to steps (a) to (c), wherein edited changes automatically take effect on the control program and on the control code. This input method is intended to assist the approach and mindset of a mechanical engineer and therefore to facilitate considerably the input for a mechanical engineer.
It could thus be helpful to provide a method of programming the control of a multiaxis forming machine, the method being particularly adapted to the needs and viewpoint of the machine operator and allowing intuitively understandable and flexible programming. In addition, a system suitable to carry out the method is also needed.